Traffic signal



Aug. 4, 1942. E, GRUVER TRAFFIC SIGNAL Filed June 27, 1940 3 Sheets-Sheet l Aug. 4, 1942.

E. GRUVER TRAFFIC-SIGNAL Filed June 27, 1940 3 Sheets-Sheet 2 I 1 I I A20 3M far] ruzrer awn "4 Aug. 4, 1942. E. GRUVER TRAFFIC SIGNAL Filed June 27, 1940 5 She'e t s-Sheet 3 Ea 1'1 grill 6 Patented Aug. 4, 1942 UNITED STATES PATENT OFFICE TRAFFIC SIGNAL Earl Gruver, Hillsboro, Ohio Application June 27, 1940, Serial No. 342,782

6 Claims.

This invention relates to an improved trafiic signal for street and highway intersections for directing the movement of traflic across such intersections, and more particularly to a novel traflic signal having means for indicating the unexpired period of a given signal to warn operators of vehicles approaching the intersections, how long before the signal will be changed.

More particularly, it is an aim of the invention to provide a traflic signal of very simple construction requiring only two lamp bulbs, which are alternately energized, for directing the movement of vehicles, from a number of directions, across an intersection.

Still a further aim of the invention is to provide an illuminated traflic signal having novel means for indicating the unexpired period of stop and go signals to warn motorist of a change in the signal to enable the intersection to be cleared by the time of a change of the signal to thereby eliminate the need of a caution light and the delay caused thereby, and thus speed up traflic.

Still a further aim of the invention is to provide a traffic signal having means for indicating the unexpired term of stop and go signals to enable vehicle operators to stop before reaching an intersection where a go signal is about to be changed to a stop signal and to enable operators of vehicles waiting at the intersection to be prepared to move when a stop signal changes to a go signal.

- Other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings, which illustrate a preferred embodiment of the invention, and wherein:

Figure 1 is a side elevational view of a traffic signal,

Figure 2 is a view similar to, and taken at a i right angle to Figure 1,

Figure 3 is an enlarged longitudinal, vertical sectional view taken substantially along the plane of the line 33 of Figure 1,

Figure 4 is an enlarged vertical sectional view taken substantially along the plane of the line 4-4 of Figure 3,

Figure 5 is an enlarged transverse, horizontal sectional view taken substantially along the plane of the line 55 of Figure 2,

Figure 6 is an enlarged vertical sectional view taken substantially along the plane of the line 6-6 of Figure 4,

Figure 7 is a horizontal sectional view taken substantially along the plane of the line 1-1 of Figure 6,

Figure 8 is a diagrammatic view showing the electric circuit of the trafiic signal, and

Figure 9 is an enlarged vertical sectional view taken substantially along the plane of the line 99 of Figure 3. Referring more particularly to the drawings, wherein like reference characters designate like or corresponding parts throughout the different views, I 0 designates generally a traffic signal, comprising the invention, which includes a casing H, which, in the embodiment as disclosed, is substantially rectangular in cross section as best seen in Figure 5. The casing I I includes the four sides I2, the bottom l3 and top I4. One of the sides [2 is swingably mounted on the casing H by means of the hinges I5 to form a door I6 which is normally held in a closed position by means of a latch or look IT. The door It may be opened to provide access to the interior of the casing H, to repair or replace parts disposed therein, as will hereinafter become apparent. Each of the sides I2 is provided with two longitudinally spaced openings I 8, in each of which openings is mounted a colored translucent pane I9. The panes I9 are retained in position by means of the channel portions 20, in which they are mounted, and which open inwardly of the openings 3. One of the openings 18 of each of the sides 12 is provided with a red pane and the other opening thereof is provided with a green pane to form the red windows 2| and the green windows 22.

A plurality of bolts 23 are secured to the lower end of the bottom I3 by means of nuts 24. The bolts 23 project upwardly into the casing H and are connected at their upper ends by means of other nuts 24 to a partition 25 which is supported thereby transversely of the casing II and between the upper and lower openings 18, to divide the easing into a lower compartment 26 and an upper compartment 21. As best seen in Figures 1 and 2, the side l2, which forms the door l6, and the side opposite thereto, is provided with upper red windows 2! and lower green windows 22, while the sides I 2 which are disposed at right angles to the door I6 are provided with upper green windows 22 and lower red windows 2|, so that the compartments 25 and 27 are provided with alternately arranged opposed pairs of windows of two different colors.

A lamp socket 28 is secured to each side of the partition 25 to mount the lamp bulbs 29 and 30 which are disposed in the compartments 26 and 21, for illuminating the windows 2| and 22 thereof. An electric motor 3| is mounted in the casing adjacent the top I4 by means of a bracket 32. The motor 3| is provided with a driven shaft 33 to which are keyed a pair of spaced sprocket wheels 34. A shaft 35 is rigidly secured, at one end, to the motor 3| and is disposed beneath and substantially in a vertical plane with the shaft 33. A pair of sprocket wheels 36 are rotatably mounted on the shaft 35. The complementary sprocket wheels 34 and 36 are connected by means of the corresponding chains 31. A rod 33 is secured in any suitable manner to complementary links of the chains 31 and has a free end extending outwardly from the chain 31, away from the motor 3!, for a purpose which will hereinafter become apparent.

Referring particularly to Figure 5, the casing H is provided with guides 40, disposed in the corners thereof, which are angular in cross section and which extend longitudinally of the casing A rectangular frame 4| is mounted in the casing between the sides l2 and the partition 25. The frame 4| is provided with. perpendicular corner members 42, which are angular in cross section, to correspond to the guides 40, which are slidably mounted in said guides to slidably mount the frame 4| longitudinally of the casing The frame 4| is provided with a plate 43 in its upper end, which extends there across at right angles to the shafts 33 and 35 and which is provided with a longitudinal slot 44 in which is loosely mounted the end 39 of the rod 38. The frame 4| is provided with open sides. The lower portions of the four open sides of the frame 4| are covered by means of a strip 45, which is carried in the frame 4| by means of the channel portions 46, and which extend therearound. The strip 45 contains sufiicient dark or black pigments to render it semiopaque, for a purpose which will hereinafter become apparent.

A block 41 of insulating material is mounted in the'casing II on one of the sides i2. The block 41 is disposed in the upper part of the casing beneath and adjacent to the motor 3|. As best seen in Figures 6 and 7, the block 41 is provided with the contact posts 48 and 49, spaced contact elements 59 and and a contact post 52. A switch blade 53, of conducting material, is pivotally mounted-on a bolt 54, adjacent one end thereof.. The bolt 54 is secured to the block 41 and carries a coil spring 55 and a nut 56 against which one end of the spring 55 bears. The opposite end of the spring 55 bears against the blade 53 to frictionally hold the blade in engagement with a strip 51 of conducting material which is embedded in the block 41 and which is connected to the bolt 54 and the contact post 52. The blade 53 extends substantially beyond one end of' the block 41 and is provided on its free end with a casing 58 of insulating material which is disposed in the path of a pair of spaced lugs 53 and 63, which are carried by the frame 4|.

Referring to Figure 8, a conductor 3| leads from a source of electric current, not shown, to the contact post 52, through the plate 51, to the blade 53. A conductor 62 leads from the contact 50 through the contact post 48 to the lamp bulb 29, and a conductor 63 similarly leads from the contact 5|, through the contact post 49 to the lamp bulb 33. Branch conductors 64 lead from the lamp bulbs 23 and 36 to a ground wire 65 which leads back to and is grounded at the source of the electric current. The ground conductor 65, adjacent said source, is provided with a switch 66. A branch conductor 61 leads from the conductor 6| to the positive side of the motor 3|. A branch conductor 68 leads from the negative side of the motor 3| to the ground wire 65, so that whenever the switch 66 is closed the motor 3| will be in operation to turn the shaft 33 and through the sprockets 34 and 36 to drive the chains 31 to move the rod 38 continuously around the pairs of sprockets 34 and 36.

This endless movement of the rod 38 will cause the frame 4| to be raised and lowered relatively to the casing The motor 3| is adapted to be driven at a very slow speed or the shaft 33 is geared down relatively to the motor 3|, by means not shown, so that it will take approximately one half a, minute for the frame to move.

from its lowermost to its uppermost position, or conversely. As will hereinafter become apparent, this period of time may vary depending upon conditions and the desirability for maintaining the signal for a longer or shorter period. Just prior to when the frame 4| has reached its lowermost position, as illustrated in Figure 3, the lug 59 will have contacted the casing 58 to move the switch 53 from its dotted line position, as seen in Figure 6, to its full line position to thereby move the switch 53 out of engagement with the contact 50 and into engagement with the contact 5|. When the switch 53 is thus moved out of engagement with the contact 53 the circuit of the lamp bulb 29 is broken, and when the switch 53 contacts the contact 5| the circuit to the lamp bulb 30 is completed to energize the bulb 30 and thereby illuminate the compartment 21 and the windows 2| and 22 thereof for showing green signals and red signals at right angles to the green signals and red signals previously illuminated by the lamp bulb 29 when the compartmerit 26 was illuminated. As the rod 38 moves upwardly, the frame 4| will be drawn upwardly to cause the strip 45, which forms a curtain, to gradually cover the increasing portions of the upper windows 2| and 22. The semi-opaque curtain will darken these upper windows 2| and 22 1 sufficiently so that the portions thereof covered by the curtain 45 will be of a darker shade than the exposed portions for indicating the elapsed time of the illuminated signal and the unexpired period. When the rod 38 and frame 4| have reached their fully raised positions the windows 2| and 22 of compartment 21 will be completely covered. As the frame 4| approaches its fully raised position, the lugs 60 will engage the casing 58 of the switch arm of blade 53 to move it upwardly, and out of contact with contaot 5| and into engagement with contact 5|! to thereby break the circuit to the lamp bulb 30 and complete the circuit to the lamp bulb 29 to illuminate the compartment 26 and its windows 2| and 22 which, being disposed at right angles, respectively, to the windows 2| and 22 of compartment 21 will change the signal being given so that the newly illuminated go signals will be at right angles to the previously illuminated go signals and the newly illuminated stop signals will be at right angles to the previ-- ously illuminated stop signals. As the frame moves downwardly the curtain 45 will shade the windows 2| and 22 of the lower compartment 26- to indicate the expired and unexpired" period of the illuminated signals, in'the same manner as heretofore described.

It will thus be seen that the traffic signal l0 provides means for indicating the unexpired term of the illuminated signals thereby eliminat ing he necessity of providing a caution signal. In this manner the movement of trafiic will be speeded up due to the fact that the periods when a caution signal would otherwise be illuminated, are eliminated.

In the embodiment of the invention, as disclosed, a hook E9 is secured to and projects upwardly from the top [4 for engaging a hanger 10 which may be connected to any suitable supporting means for suspending the traffic signal 10 above an intersection of cross streets or highways. Obviously, the traffic signal It! could be mounted on a pedestal, or other similar supports, not shown, and if desired a plurality of the traflic signals could be mounted at intersections on poles at the corners of the intersections, or on the corners of buildings, disposed adjacent the intersections, in which cases the traffic signals instead of having windows in four sides, could be provided with windows in only one or two sides to function in the same manner. Where a plurality of trailic signals are thus provided at a single intersection, all of the traffic signals could be connected in a single circuit to operate simultaneously. The master switch 56 is provided for shutting off the traffic signal iii during certain hours of the night, for example, when traffic does not justify the use of the signal.

Various modifications and changes are contemplated and may obviously be resorted to as only a preferred embodiment of the invention has been disclosed.

I claim as my invention:

1. A traffic signal comprising an elongated casing having an opening adjacent each end thereof, partitions dividing the ends of said casing into compartments, one of said openings communicating with each of said compartments, panes of colored glass covering said openings, said panes being of different colors, means for illuminating each of said compartments alternately, a semi-opaque shade movable relatively to said casing, between the illuminating means and the openings for, to shade varying portions of the openings for indicating the unexpired period of an illuminated signal.

2. A traflic signal as in claim 1, said shade including a frame slidably mounted in the casing, a semi-opaque strip carried by said frame and movable relatively to said compartments between the complementary openings and the illuminating means, an electric motor mounted in said casing and having a driven shaft, and means connecting said driven shaft to said frame whereby the continuous rotation of the shaft will impart a reciprocating motion to the frame.

3. A trafiic signal comprising an elongated casing, said casing being rectangular in cross section, each of the sides of said casing being provided with a pair of longitudinally spaced windows, a partition dividing said casing'into end compartments, said partition being disposed between the windows in each of said sides to provide a window for each of said compartments in each of the sides of the casing, the windows of each of said sides being of different colors, the complementary windows on opposite sides of the casing being of corresponding colors, means for illuminating the windows in each of said compartments alternately, a frame slidably mounted in said casing, and a curtain carried by said frame and disposed between the illuminating means and the windows for changing the shade of the color of the portions of the illuminated windows covered by the curtain for indicating the elapsed time interval of an illuminated signal.

4. A trafiic signal comprising a casing provided with compartments each having a colored trans lucent window, illuminating means in each compartment for illuminating the window thereof, means for energizing the illuminating means, a switch for controlling the energizing means for alternately energizing the illuminating means, a frame slidably mounted in said casing, a curtain carried by said frame and disposed between the illuminating means and the windows for changing the shade of the portions of the illuminated windows covered by the curtain for indicating the elapsed time interval of an illuminated signal, an electric motor mounted in said casing provided with a driven shaft, a sprocket wheel keyed to said shaft, a fixed shaft disposed beneath said first mentioned shaft and provided with a sprocket wheel rotatably mounted thereon, a chain trained over said shafts, a rod fixed to and projecting from a link of said chain, and said frame being provided with an elongated slot in which said rod is slidably mounted, said chain being movable for reciprocating the frame relatively to the casing.

5. In a trafiic signal, sets of colored, translucent portions, the translucent portions of each of said sets being of a plurality of colors, a common means for simultaneously illuminating the translucent portions of each of the sets thereof, each of which forms an illuminated signal, said sets of translucent portions being alternately illuminated, and a single semi-opaque member, associated with said sets of translucent portions and movable relatively thereto for simultaneously shading corresponding parts of the translucent portions of each set and for alternately shading the translucent portions of the different sets, said member being movable for varying the areas of shaded parts for indicating the expired and unexpired terms of the illuminated signals.

6. A signal as in claim 5, said semi-opaque member comprising a frame, substantially rectangular in cross section, means for reciprocating the frame betwen the sets of translucent portions and the illuminating means, and a semiopaque shade extending around the frame and carried thereby.

EARL GRUVER. 

